When customers use Coupon Codes with large Orders (multiple sessions or registrants), the Coupon discount may not always apply in the originally intended way.  The following scenarios showcase how Coupon Codes in CCM behave:

Scenario 1:
1.  Person registers for a Session or Sessions
2.  Coupon Code is entered immediately at the cart page
3.  (Optional) Person clicks the Add a Registration button to add more Sessions 

Result:  The current registration and all subsequent registrations will receive the discount

Scenario 2:
1.  Person registers for a Session or Sessions
2.  Person clicks the Add a Registration button to add more sessions 
3.  Coupon code is entered after the subsequent registration
 
Result:  The Sessions selected in the second round will receive the discount, but those selected in the first round will not

Scenario 3:
1.  Person registers for a Session or Sessions
2.  Person clicks the Add a Registration button to add more Sessions 
3.  Coupon code is entered after registering for all desired Sessions
 
Result:  Discount is applied to only the last Session

To Add or Remove Discounts, please use the following links:
Apply an Internal Discount to an Existing Order
Removing a discount